The method that a client system will use to resolve NetBIOS names to IP addresses relies on what is referred to as its node type. Microsoft supports 4 main node types, and these control the order in which resolution attempts will take place. By default, a system not configured with a WINS server address will be configured for B-node, and with a WINS server address will be configured for H-node. Most often, node type is configured as a DHCP option, but it can also be configured on individual systems via a Registry change. The 4 main node types are listed below. Note that a client system always checks the NetBIOS name cache first. The Hex values of the node types are listed for the purpose of registry modification. To find out which node type a client is using, run ipconfig /all
B-node (Broadcast) – this method uses a broadcast to resolve names. In Microsoft land, this is actually called ‘enhanced B-node’, since if the broadcast fails, the client will attempt resolution via the LMHOSTS file. Value is 0x1.
H-node (Hybrid) – this method first tries resolving the name via a WINS server, and then attempts B-node methods if unsuccessful. Value is 0x8
M-node (Mixed) – this method first attempts to resolve names via broadcast, followed by an attempt at querying a WINS server should that fail. This is often used in environments where a WINS server is across a WAN link. Value is 0x4
P-node (Peer-to-peer) – this method uses a WINS server for resolution, and never broadcasts. Value is 0x2
